RAP has evolved a lot since that time, so I doubt that this reading will
set you on the right track. With RAP 2.0, the protocol, lots of API
changes, and our transition to a platform for remote applications, most
of the concepts explained in this book are meanwhile outdated.

The best information you can currently get is our online documentation
[1] including the New and Noteworthy pages [2] and the developer's guide
[3].